Abstract: The secure messaging system of the invention encrypts an electronic document using a symmetric key and transmits the encrypted document and related message parameters to a recipient whose identity is then authenticated by a web server. The web server dynamically regenerates the symmetric key from a hidden key and from the message parameters accompanying the encrypted document, and thus avoids having to maintain a central repository of encrypted documents as required by typical “post and pick-up” encrypted messaging systems. Further, an audit trail produced while practicing the invention provides timestamped message digest data for a plurality of time intervals, where the message digests for adjacent time intervals are computationally linked together. The audit trail effectively enables timestamped message digest data to verify not only the existence of a document during a first time interval, but also to verify the existence of documents encountered in a prior time interval.

Abstract: A technique for providing message authenticity includes accepting transaction information, accepting a first data item used for authenticating an originating user, cryptographically processing the transaction information using only a second data item, wherein the entropy of the first data item is less than the entropy of the second data item, and authenticating the originating user using the first data item. The first data item can be a sequence of digits corresponding to those displayed on an external device, such as, for example, an RSA authorization token, credit card, etc. In general, the first data item will be a short alphanumeric string and the second data item will generally be much larger, e.g., a 128 bit sequence to be used principally for data authentication. According to another aspect of the present invention, consequential evidence of the transaction may be secured to provide after-the-fact evidence of the transaction.

Abstract: A method for protecting an item of software, wherein at least one challenge means is associated with said protected item of software, and at least one response means accesses one private keying material. The challenge means has no access to said private keying material. The response means proves to the challenge means that the response means has access to the private keying material using an asymmetric probabilistic proof, e.g., zero knowledge proof. The challenge means validates this proof using the public keying material that corresponds to the response means' private keying material.

Abstract: A method for protecting an item of software, wherein at least one challenge is associated with the protected item of software, and at least one response accesses one private keying material. The challenge has no access to the private keying material. The challenge and the response are generating shared secret information, respectively, in accordance with an asymmetric confidentiality scheme. The response proves that it discovered the shared secret and the challenge validates the proof. The challenge proof validation procedure uses the public keying material that corresponds to the response private keying material.

Abstract: The secure messaging system of the invention encrypts an electronic document using a symmetric key and transmits the encrypted document and related message parameters to a recipient whose identity is then authenticated by a web server. The web server dynamically regenerates the symmetric key from a hidden key and from the message parameters accompanying the encrypted document, and thus avoids having to maintain a central repository of encrypted documents as required by typical “post and pick-up” encrypted messaging systems. Further, an audit trail produced while practicing the invention provides timestamped message digest data for a plurality of time intervals, where the message digests for adjacent time intervals are computationally linked together. The audit trail effectively enables timestamped message digest data to verify not only the existence of a document during a first time interval, but also to verify the existence of documents encountered in a prior time interval.

Abstract: A software rental system and method are provided having at least one rented program permitting at least one service to a customer with a customer's response means. The rented program has no access to a customer's private keying material. Using asymmetric cryptography, the customer's response means proves to the rented program that the customer's response means has access to the customer's private keying material. The rented program does not permit the at least one service to the customer unless the proof is successful.

Abstract: A method of manufacturing a disc drive actuator is provided. The method includes manufacturing a disc drive actuator and machining a peripheral surface of the actuator. The peripheral surface is machined to obtain a desired profile dimension and thereby reduce variations in resonance characteristics from one actuator to the next.

Abstract: A computer system is provided having a protection mechanism for protecting the contents of a file. The protection mechanism has at least one Viewer program, at least one challenge associated with the Viewer program and the file, and at least one response with private keying material that it can access. The challenge has no access to the private keying material. The response can prove that it has access to the private keying material by interacting with the challenge using an asymmetric cryptographic scheme. The challenge can instruct the Viewer program to avoid using some or all of the file's content unless the proof is successful.

Abstract: A method for protecting an item of software, wherein at least one first challenge means is associated with said protected item of software, and at least one first response means accesses one private keying material. At least a third means (either challenge or response also exists). The first challenge means has no access to the said private keying material. The first response means proves to the first challenge means that the first response means has access to the private keying material. The first challenge means validates this proof using the public keying material that corresponds to the first response means' private keying material.

Abstract: An actuator assembly for a disc drive includes an E-block supported by a spindle for rotation about an axis and having an actuator arm supporting a transducer. An elongated yoke arm extends from the E-block. A motor rotates the E-block about the axis to position the transducer adjacent a selected track on the recording disc. The motor includes a voice coil supported by the yoke arm. A stop mechanism defines at least one of the inner and outer tracks of the disc and comprises at least one stop pin mounted to the disc drive housing and a stop surface on a distal end of the yoke arm for engaging the stop pin.

Abstract: The instability of a cage in a precision ball bearing at high speeds may be eliminated by controlling the position of the cage. The control of a position of a cage is accomplished by forming three ball pockets or holes in the cage for the balls of the ball bearing assembly to a dimension that will result in a tight running fit between the ball and the ball pocket. A tight running fit between the ball and the cage is found in three of the ball pockets in a ball bearing assembly while the diameter of the large ball pockets or other remaining ball pockets is enlarged to provide a clearance between the balls and the cage which is at least twice the clearance between the ball and the guide ball pocket having the tight running fit, and preferably three to five times that clearance. When properly lubricated, the tight running fit will insure stabilization and control of the cage so that the cage remains stable at high rotational speeds.